Activity replenishment and in situ activation for enzymatic co2 capture packed reactor

Abstract

A method for CO2 capture may include operating a packed reactor comprising a reaction chamber containing packing including immobilized enzymes, by contacting a CO2 containing gas with a liquid solution in the reaction chamber to produce an ion-loaded solution and a CO2 depleted gas by an enzymatically catalyzed hydration reaction; monitoring enzyme activity of the immobilized enzymes; at a low enzyme activity threshold (i) stopping operation in the packed reactor, and (ii) replenishing the enzymatic activity by providing an enzyme replenishing solution into the packed reactor to contact the packing and provide a replenishing amount of the immobilized enzymes; and recommencing operation in the packed reactor for CO2 capture using the replenished immobilized enzymes. A corresponding system may include a packed reactor and an in situ enzyme supply device for supplying active enzyme within the reactor. The enzyme supply device may include spray nozzles with various configurations.

Description

FIELD OF INVENTION[0001]The present invention generally relates to the field of CO2 capture or CO2 absorption. The present invention more particularly relates to the field of enzymatically enhanced CO2 capture from CO2 containing gas using a packed reactor and enzyme activity replenishment techniques.BACKGROUND[0002]Treatment of CO2 containing gas has in some cases used the enzyme carbonic anhydrase to enhance the hydration reaction of dissolved CO2 into bicarbonate and hydrogen ions in an absorption solution. The absorption solution is then treated through precipitation or desorption in order to produce precipitated mineral solids or a relatively pure CO2 stream for geologic sequestration or reutilization.[0003]Packed reactors having a reaction chamber filled with packing have also been used in the context of CO2 capture.[0004]In some cases, carbonic anhydrase has been immobilized with respect to packing material in a packed reactor in order to remove CO2 from an incoming gas.[0005...

AI Technical Summary

Benefits of technology

The patent text describes a method for capturing CO2 from a gas stream using packed reactors. The method includes operating multiple reactors in parallel to maintain CO2 capture while one reactor undergoes a regeneration process. The method also involves using an enzyme replenishing solution to provide a thin coating of immobilized enzymes onto the packing material. The replenished coating does not significantly increase the size of the packing. After the regeneration process, a drying time is allowed for the immobilized enzymes. The use of CO2-containing gas may enhance the immobilization of the enzymes or their distribution onto the packing material.

Problems solved by technology

However, using carbonic anhydrase immobilized to packing in a packed reactor has a number of challenges.

For example, over time the carbonic anhydrase present in the packed reactor loses activity notably due to denaturing of the enzyme.

While some immobilization materials and techniques can prolong activity levels of the enzyme, over time the enzyme activity reduces and will eventually no longer significantly contribute to the catalysis of the CO2 hydration reaction.

For instance, consistent process operation over time can be difficult.

In addition, removing deactivated packing from a reaction chamber and replacing it with packing that has active enzyme is inefficient, costly and causes unwanted downtime for processing CO2 containing gas.

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